ABB · AC500
The PROFIsafe watchdog timer has expired, meaning the safety I/O module did not receive a valid PROFIsafe telegram within the expected timeframe. This indicates a communication interruption or delay that prevents the safety system from functioning correctly, leading to a safe state.
Click steps to track your progress.
1. Check the network status LEDs on both the safety CPU and the safety I/O module for communication errors or link failures.
2. Verify the physical PROFIBUS/PROFINET connection and check for loose cables or damaged connectors.
3. Review and potentially increase the F_WD_Time parameter in the safety configuration to allow for network variations.
4. Monitor the network traffic and bus cycle time using a network analyzer to identify excessive delays or telegram loss.
5. If all communication path components are verified, perform a firmware update on the safety I/O module or replace the module.